Banjo fittings are widely used to make fluid connections when fluid must be supplied to a component through a 90 degree change of direction or other similar reorientation of fluid flow. Banjo fittings are so named because of their shape, which usually includes a tube brazed onto a round component, giving rise to a substantially banjo-shaped assembly. Unlike other components that perform the same function, banjo fittings can be readily assembled with power tools and offer inherent assembly benefits in applications where time to assemble and ease of access to components are important considerations.
FIGS. 1A and 1B show a prior art banjo fitting 100 comprised of a block 118 with an opening 120 through which a bolt 102 is inserted. The combination of block 118 and bolt 102 is assembled to make a fluid connection by tightening the bolt 102 to a fluid port 104 of a component. When assembled, a passageway 112 through the block 118 is placed in fluid communication with the port 104 through a passageway 114 in the bolt 102. To minimize leakage, copper washers 116 are generally placed on opposite sides of the block 118 to provide a high pressure seal on both sides of the block 118 when the bolt 102 is tightened.
One drawback of the prior art banjo fitting 100 is the extent of assembly that is required. Specifically, because separate washers 116 are used, the bolt 102 must first be inserted through one washer, then the block 118, and then a second washer prior to tightening the bolt 102 to the port 104. Pre-assembly of the washers 116, block 118 and bolt 102 is not feasible in the prior art banjo fitting 100. Accordingly, the washers 116 may become separated or lost during assembly.
Another drawback of the prior art banjo fitting design 100 is the need to widen or hollow out a central chamber 110 of the block 118. Because the bolt 102 of the prior art banjo fitting 100 is turned during tightening, the bolt passageway 114 may not be directly aligned with the block passageway 112 at the conclusion of assembly. To overcome this problem of misalignment, the central chamber 110 of the block 118 is hollowed out or widened so that the bolt passageway 114, regardless of angular orientation, is always in fluid communication with the block passageway 112 through the central chamber 110. The process of widening or hollowing out the central chamber 110 of the block 118 is expensive and time consuming.
Accordingly, a new banjo fitting is desired that addresses the problems associated with the prior art design.